Source Outdoor Vim 2L Hydration System Pack Lightweight hydration pack with 2-liter Widepac hydration bladder; ideal for trail running, hiking, and more Zippered compartment and side net pockets for carrying just the essentials Mesh shoulder straps; adjustable sternum strap; 70D ripstop nylon construction; air pump loop Taste-free reservoir with maintenance-free Glass Like liner prevents bio-film build-up Rounded Helix bite valve delivers a full flow with just a soft bite; built-in safety shutoff mechanism